The immediate aim of this research is to study the molecular events of cellular transport, in order to achieve the long-range goal of understanding important physiological functions such as intestinal absorption, renal clearance as well as certain disease states brought about by abnormalities in cellular transport. We will attempt to isolate membrane-bound transport components from bacteria and various eukaryotic cells such as Ehrlich ascites tumor cells, lymphocytes, lymphoblasts and 3T3 mouse cell lines. Membrane vesicle preparations will be made from both animal and bacteria cells comparing transport activities with those of intact cells. The membrane preparations will be solubilized using detergents and phospholipids and subjected to separation techniques such as gel electrophoresis. Affinity chromatography and double labeling techniques will be explored as potential methods for determining binding activity for the lower affinity receptor sites of mammalian cells. we will investigate the energy-coupled step in amino acid transport in bacteria using various mutants that have knoen defects in the transduction of metabolic energy. Finally, the relationship of transport activity for amino acids to the growth rate of bacteria will be investigated.